Monday, April 28, 2008

New Mercury features get artists' names

Just four months after the Messenger spacecraft flew by Mercury for the first time, the International Astronomical Union has approved names for the first batch of new features photographed by the instrument (see a map with the named features here). The IAU even approved new rules for naming fossae, sunken valleys with faults on both sides, since these were not seen by Mariner 10 when it flew by Mercury three times between 1973 and 1975.

That quick response is a welcome relief after IAU's lengthy battles over what to call icy bodies in the outer solar system, which led to the still-controversial redefinition of the word "planet."

Messenger principal investigator Sean Solomon of the Carnegie Institution of Washington was particularly happy because his team has just finished their first round of papers on the flyby, and they can call their discoveries by their formal names. That wasn't possible for the big objects in the distant, icy Kuiper Belt that caused the whole fuss over the definition of a planet. It took more than a year before the biggest "dwarf planet," Eris, could formally be named by its discoverers.

The rules for naming features on planets, satellites, and asteroids can be elaborate. The IAU rules state craters on Mercury can be named after "deceased artists, musicians, painters, and authors who have made outstanding or fundamental contributions to their field and have been recognized as art historically significant figures for more than 50 years."

The new rules say that fossae should be named after "significant works of architecture." The Messenger team picked the still-used Pantheon temple built in Rome in the second century AD, since both the building and the fossae "feature a central circular feature and radiating texture."

One crater is named after Nobel laureate Pablo Neruda, the Chilean poet and politician. But most of the Messenger team's choices are far from household names for most of us. The crater Apollodorus was named after the second-century Greek architect credited with designing the Pantheon temple. Eminescu (shown) was named after poet Mihail Eminescu, considered the "godfather" of the modern Romanian language. Another crater was named after Leetile Disang Raditladi, credited with founding Botswana's nationalist party in 1959.

But it's worth noting that the rules are not enforced with an iron rigidity. Raditladi died in 1971, so perhaps there's hope for other famed artists and musicians who died less than 50 years ago. When will we start hearing of craters named for Brian Jones, Janis Joplin, and Jim Morrison?

And shouldn't there be craters named after old-time science-fiction writers like Cyril M. Kornbluth (who died 50 years ago last month) or E. E. "Doc" Smith?

Friday, April 25, 2008

Billion-dollar cosmic ray probe still grounded

A $1.5 billion experiment to study speeding particles called cosmic rays is still stuck on the ground, with no way to get to the International Space Station, where it was intended to operate.

The Alpha Magnetic Spectrometer (AMS) was designed to study the composition and origins of the charged cosmic rays, which are thought to originate in high-energy events such as supernova remnants and the magnetic cocoons around violent galaxies. It will also look for particles of antimatter and for indirect signs of particles of dark matter, the mysterious invisible material that makes up most of the mass in the universe.

Most of the funding for AMS came from European and Asian countries that partnered with the US on the project. NASA made a promise back in 1995 to haul the 7-tonne experiment to the International Space Station (ISS) on a space shuttle flight.

But in the wake of the loss of the shuttle Columbia and the decision to retire the space shuttle fleet in 2010, NASA changed its mind, saying there was not enough room on remaining flights for AMS.

At a hearing of a congressional committee on space and aeronautics on Thursday, committee member Nick Lampson criticised the situation. "If we say we're going to do something, we ought to keep our word," he said.

He asked NASA associate administrator for space operations, Bill Gerstenmaier, if there was any way AMS could still be squeezed onto a shuttle flight.

"We don't see a spot in the current shuttle manifest's remaining 10 flights to fly the AMS," Gerstenmaier said. The only way to get AMS on one of the remaining shuttle flights would be to leave some important spare parts for the space station on the ground, he said.

"The problem is if I took those spares off and replace [them] with AMS, then I've hurt the basic infrastructure that's on board [the] space station," he said.

If the infrastructure breaks down and there are no spares, then even if AMS were up there, it might not be able to function, since it relies on the space station for power and other support, Gestenmaier said.

I don't envy NASA for the tough spot it's in, straining to finish deliveries to support the space station with barely enough shuttle flights left to do so. On the other hand, it seems a real shame to throw away a $1.5 billion piece of hardware.

There is still a chance that AMS could make it to space. Other options for delivering it to orbit have been proposed, according to a New York Times article, including launching it separately on a rocket of its own rather than on a shuttle flight, and perhaps revamping it to allow it to operate as an independent satellite, without the need to plug into the space station. With a shuttle delivery looking increasingly unlikely, these ideas may be the only hope for AMS.

Thursday, April 24, 2008

Jazz song uses Saturn sounds

Jazz musician and composer Jeff Oster has incorporated the eerie sounds of Saturn's auroras into a jazz piece called "Saturn Calling", which won a 2008 Independent Music Award in the New Age category.

Oster, a space enthusiast, got the idea for the song while listening to the ethereal sounds of Saturn's auroras. You can listen to the piece here, and check out sound files made from Cassini spacecraft measurements of things like magnetic fields and radio waves in Saturn's environment.

The sounds of Saturn's auroras help set an imaginative, other-worldly tone for the piece, and I think "Saturn Calling" makes a great soundtrack for viewing some of the astonishing images that Cassini has taken.

Hubble reveals a zoo of galaxy mergers

Wednesday, April 23, 2008

Cherry seeds to take out-of-this-world trip

Hundreds of cherry seeds will travel to the International Space Station in October as part of a project by the Japan Aerospace Exploration Agency (JAXA). Once returned to the ground, the seeds will be studied for changes due to microgravity, and some will be planted, according to an Agence France-Presse story.

Cherry blossom mania sweeps Japan each spring, where it is a popular tradition to hold picnics beneath the trees when they flower. One beloved tree, called Takizakura, or "cascade cherry blossoms," located in the town of Miharu, gets 300,000 visitors each year.

School children will collect 200 seeds from Takizakura and these will be sent to the space station, along with seeds from other trees. The seeds will stay in space for six months aboard the Japanese laboratory that forms part of the station, according to AFP.

Some of the seeds will be studied to see how their stay in space affected them and some will be planted. "Since the seeds will be returned with a certificate that they have gone to space, we hope to use them to promote tourism here while drawing children's interest in science," a Miharu town official told AFP. "We are very proud that our tree was selected among many cherry blossoms that represent Japan."

China has previously launched fruit, vegetable, rice and cotton seeds into space and returned them to Earth. Some said the seeds produced unusually high yields when planted, though researchers contacted by New Scientist were sceptical of the claims.

I've never experienced the cherry blossom season in Japan, but a friend of mine who has tells me some people camp out overnight to reserve choice spots under the trees. The competition for spots under trees grown from space seeds is sure to be especially intense.

Monday, April 21, 2008

Whimsical 'N-prize' to spur ultra-cheap space launches

The challenge: put a tiny satellite that weighs less than 19.99 grams - the weight of about two British pound coins or four US quarters - into orbit on a budget of only 999.99 pounds (about $2000). The satellite must complete nine orbits around the Earth, and this must somehow be verifiable from the ground.

The prize: 9,999.99 pounds (about $20,000).

Your chance of success: close to zero.

That pretty much sums up a new challenge put forth by Paul Dear, a biologist at the Medical Research Council Laboratory of Molecular Biology in Cambridge, UK, who apparently really likes the number 9.

Called the N-prize (the "N" stands for "Nanosatellite" or "Negligible Resources"), the purse will be awarded to the first person or group to complete the challenge before 19:19:09 on the 19th September 2011. Importantly, the weight restriction does not apply to the launch vehicle used to put the satellite in orbit.

"Somehow, a bargain basement budget of 999.99 pounds just seemed right, and everything else followed - the edge of space is about 99 kilometres up, and nine orbits seemed like a reasonable target: any more would just be showing off," Dear said.

Dear gleefully admits that he thinks the task is "well-nigh impossible." "Your job is to work around that 'almost,'" he said.

Dear first proposed his idea on Halfbakery.com, a website devoted to speculative (and mostly wacky) ideas. One Halfbakery.com commenter known as "globaltourniquet" responded to the challenge by paraphrasing the movie Zoolander: "What is this? A space program for ANTS?!?"

But while the language of the prize is very tongue-in-cheek, Dear says he is serious, and that he really does have 9,999.99 pounds to give away. And he has now set up an official website for the challenge.

Initial responses to the task include a suggestion to attach blinking LED lights to a small satellite that might be tracked with ground telescopes.

Dear said some useful insight could be gleaned from the past. In the 1950s, scientists used hybrids of high-altitude balloons and lightweight rockets - called "rockoons" - to explore the edge of space on the cheap. The idea was to use the balloon to cover most of the distance into space and then fire the rocket to finally reach space.

"Of course, once you're there, you still have to turn the corner and get your satellite travelling sideways at about 7 kilometres per second," Dear said. "But we never said it would be easy."

Richard Branson might conduct the marriage himself, the Virgin spokesperson said. In 2007, he officiated over an in-flight wedding aboard a Virgin America jet between the company's marketing director and his bride.

The Virgin Galactic marriage would be the first with both the bride and groom in space. But in 2003, cosmonaut Yuri Malenchenko exchanged vows from the International Space Station via a radio link with his Earth-bound bride Ekaterina Dmitriev.

I'm sure the space wedding will be an unforgettable experience for everyone involved. They will have to have a quick ceremony, though, since their voyage aboard Virgin's SpaceShipTwo will have them flying in space for only a few minutes.

Friday, April 18, 2008

Life defined

What is life? According to Sohan Jheeta, an astrobiologist from the Open University in Milton Keynes, UK, biologists have spent far too long dithering about how to define what a living organism actually is. As a result there are more than 280 definitions of life on record, and none of them really hits the mark, Jheeta says.

He sparked some lively debate about the issue at an astrobiology conference this week in Santa Clara, California, US. Jheeta says one of the most widely accepted definitions of life, and one favoured by NASA, is no good.

Life is "a self-sustaining system capable of Darwinian evolution", it goes. But Jheeta points out life isn't exactly self-sustaining - we can't live without oxygen, food and water.

Other definitions simply list attributes of life on Earth, including that it "grows". Then again, crystals and cities grow. You could add the constraint that life must also be capable of reproducing. But post-menopausal women are alive yet can't reproduce (unless they pays lots of money for IVF and tolerate much sneering from tabloid newspapers).

Jheeta says his team has come up with a new definition of life that "truly captures the essence of what all living things actually are and do". True to form for a scientific definition, it's well-considered, it's precise, and it has all the poetic elegance of a software manual:

"Life is a thermodynamically open chemical system with a semi-permeable boundary. It contains an information-based complex system with emergent properties, part of which drives a metabolism based on a proton gradient. The said gradient generates the necessary potential difference across the semi-permeable boundary. The information is heritable and coded in such a way as to allow variation and thus evolution."

"Thermodynamically open" just means that life exchanges matter and energy with its surrounding environment. A proton gradient is central to the definition, Jheeta says, because all living organisms on Earth harness them to use energy steadily rather than being swamped by it all at once.

But why do we really need a definition of life? Jheeta says it's important for the design of space missions seeking life on other worlds. Sometimes they look for amino acids or other biological chemicals. But on that basis, the chemicals cupboard in a laboratory would seem to be teeming with life while the middle of the Atlantic Ocean might look dead as a dodo.

Jheeta thinks scientists should design spacecraft that detect proton gradients instead. Admittedly, they would only detect life that's chemically similar to life on Earth. But it would be impossible to detect completely different kinds of alien life, Jheeta says, because we wouldn't know how to design the right experiment.

Let's hope the first alien we meet makes things easy by having a green pointy head and saying "take me to your leader". In the meantime, can you think of a good definition for life?

Wednesday, April 16, 2008

Neil Armstrong's 'small step' was very small indeed

What would you do if you were the first person to land on another world? When Neil Armstrong and Buzz Aldrin landed the Apollo 11 lunar module on the moon in 1969, they didn't worry about hostile aliens tracking them with laser guns, but they were concerned about walking around in an unfamiliar environment.

Stepping out on the lunar surface, however, Armstrong reported that it was "absolutely no trouble to walk around". And, surely, having travelled 380,000 kilometres to reach the moon, Armstrong and Aldrin must have been keen to explore as much of the surface as possible.

But the Strange Maps blog has turned up a fascinating map on NASA's Apollo lunar surface history site, which shows that Armstrong didn't get very far. He roamed an area smaller than a soccer pitch, and Aldrin only managed about a third of that. If you're a baseball fan, take a look at this alternative map, where NASA has plotted the astronauts' wanderings on a baseball diamond. It shows that Armstrong made it to the outfield but Aldrin barely reached first base.

Were the Apollo 11 astronauts a little timid, or perhaps overawed by the sight of the Earth in the sky? More likely they were pressed for time. Armstrong and Aldrin only had two and a half hours to explore the lunar surface, during which they scooped up more than 20 kilograms of moon rocks. They blasted off from the moon less than 24 hours after they landed.

NASA gave Apollo 12 astronauts more leeway. With nearly 8 hours on the lunar surface split between two sessions, they walked hundreds of metres. Apollo 14 astronauts spent more than 9 hours on the surface and trekked to a crater 1.5 kilometres away from where they landed. The final three missions carried lunar rovers, so astronauts could drive several kilometres away from their landing sites.

Tuesday, April 15, 2008

Quantum pioneer John Wheeler dies

Physicist. Philosopher. Poet. Visionary. Guru. John Archibald Wheeler, who died April 13 at age 96, wore all of these hats in his efforts to penetrate the nature of ultimate reality.

Wheeler was equally comfortable working in the large-scale realm of gravity as he was in the fuzzy quantum arena at nature's smallest scales. Perpetually decades ahead of his time, he was one of the first physicists to consider what it might really mean to unite these two worlds, pioneering the now-thriving field of quantum gravity. Wheeler worked with Niels Bohr, his mentor, to develop the theory of nuclear fission, which led to his involvement in the Manhattan Project and later in the development of the hydrogen bomb.

He strolled Princeton streets with Albert Einstein, debating the meaning of quantum theory. With Bryce DeWitt he dared to apply the strangeness of the quantum world to the universe as a whole, founding the field of quantum cosmology and writing down the infamous Wheeler-DeWitt equation - the "wavefunction of the universe" - or as DeWitt calls it, "that damned equation". With his flair for poetry, Wheeler coined the terms "black hole" and "wormhole", words that captured the imaginations of physicists and the public alike.

Wheeler's influence on his peers and especially on his students is immeasurable. Under his mentorship, Richard Feynman developed the ideas that would eventually lead to a new approach to quantum mechanics; Jacob Bekenstein proposed that the event horizon of a black hole is a measure of entropy, an idea that led to Hawking's famous discovery that black holes radiate; and Hugh Everett formulated the "many worlds" interpretation of quantum mechanics, which suggested that reality is an endlessly branching tree of possibility.

Intellectually fearless, Wheeler kept his eye on the Big Questions, not only the whats but the whys. "Why the quantum?" he liked to ask. For Wheeler, it was not enough to say that quantum mechanics works - he wanted to know what was behind it.

Einstein said, "God doesn't play dice." Wheeler accepted that God does play dice, but he demanded to know the rules of the game. "A participatory universe?" Wheeler believed that observers play a critical role in the creation of reality, and he devised brilliant thought experiments - such as his "delayed choice" experiment - to illustrate the counter-intuitive notion.

"We used to think that the world exists 'out there' independent of us," he wrote, "we the observer safely hidden behind a one-foot thick slab of plate glass, not getting involved, only observing. However, we've concluded in the meantime that that isn't the way the world works. In fact we have to smash the glass, reach in."

But the one question that kept Wheeler up at night was, "How come existence?" And that's where his legend lives on - in the countless number of physicists he inspired who continue to push the limits of thought in their effort to find the answer.

Monday, April 14, 2008

New NASA lunar institute opens its doors

Last week, on a bright and unseasonably warm Friday afternoon, NASA dedicated its new Lunar Science Institute on the campus of its Ames Research Center in Moffett Field, California. The institute's interim director, David Morrison, said it will create a scientific foundation for a "great burst of exploration" over the next decade.

The institute is housed in the former residence of the admiral at Moffett Field air base. But in recent years, the building had fallen into neglect and it has had to be extensively remodelled.

Like the admiral's quarters, NASA's lunar programme has been given a new lease of life and sense of purpose. The space agency has sent only two unmanned missions to the moon, Lunar Prospector and Clementine, since 1972. But NASA has committed itself to five unmanned lunar missions over the next six years.

China and Japan already have satellites orbiting the moon, and India will launch one later this year. "The whole world is going to the moon," said Pete Worden, director of the Ames Research Center.

But who will analyse the data produced by all these missions? During the Apollo programme, the US boasted hundreds of lunar scientists. Now, only a few of them remain, and they aren't getting any younger. "The next generation of scientists may be our most important product," said Worden. "Those are the men and women who are going to figure out the really neat things about the moon, about how to operate on the moon, and what you can do from the moon."

Worden and Morrison see the new institute as the nexus for that new community. It will be a "virtual institute" in the sense that its administration will take place in the admiral's quarters but the actual research will take place elsewhere.

NASA plans to select the first four research sites towards the end of this year. Each one will be funded to the tune of $1 to $2 million annually, and together they will employ about 50 scientists. As NASA's lunar budget grows in the build-up to a human flight to the moon by 2020, the institute will grow to include more collaborating sites, including sites in other countries. "I would anticipate that within a few years we may have five or six nodes abroad," said Worden.

On Friday, the mood was decidedly festive, with "moon pies", wine and cheese for a crowd of 200 well-wishers, including Apollo 11 astronaut Buzz Aldrin and US Congressman Mike Honda. The building was still not air-conditioned (which prompted Morrison to call the event a "thermal test" of the new facility, a joking reference to spacecraft tests).

However, it was well furnished with other delights, including an Apollo 16 moon rock, a large rotating moon globe and a mock-up of the Lunar Atmosphere and Dust Environment Explorer, a spacecraft that should launch in three years' time.

"This building looked naked one or two months ago and now it's full of life," Morrison commented. If all goes well, that will soon be true of its lunar science programme.

Dark matter mystery 'solved' - again

It's the experiment dark matter hunters love to hate. But physicists working on the DAMA (DArk MAtter) experiment might have the last laugh later this week. Rumour has it that, later this week, an Italian lab will claim to have found dark matter, at a conference in Venice, Italy.

News of the announcement has spread like wildfire among physicists here at the American Physical Society conference in St Louis, Missouri. What makes the results so controversial is that DAMA scientists have claimed to detect dark matter before, even though other experiments have failed to see it.

Now the experiment has been revamped to make it more sensitive to dark matter and renamed LIBRA. On Wednesday, Rita Bernabei of the University of Rome Tor Vergata, who leads both the DAMA and LIBRA teams, will present the first findings at the NO-VE workshop on neutrino oscillations.

The controversy dates back to 1998 when the DAMA collaboration claimed it had found evidence for particles of dark matter passing through its detector located in an underground laboratory deep within the Gran Sasso mountain, Italy. Dark matter is the invisible, mysterious stuff thought to make up nearly 90% of matter in the universe.

You might think that physicists would be overjoyed at the result. But there was a lot of scepticism. "Extraordinary results require extraordinary evidence," particle physicists would tell me. They simply didn't believe that DAMA had found the leading candidate for dark matter, particles called WIMPs that barely interact with anything.

Part of the reason is that the LIBRA and DAMA teams have always taken a different approach to finding dark matter from other experiments. They assume that the amount of dark matter flooding past our planet depends on the Earth's direction of motion, so it varies with the seasons. So the DAMA team looked for a seasonal variation in its array of sodium iodide detectors. Although the signal was small, it varied just as predicted.

But the original DAMA experiment suffered from much more background noise than other competing experiments - which have not detected dark matter. So physicists assumed that something else must be causing the seasonal variation in the DAMA detector. Perhaps the temperature of the lab was fluctuating, or the detector was picking up the decay of radioisotopes in groundwater which ebbed and flowed with the seasons. Bernabei has always stood by the DAMA result and insisted that the team checked everything they could think of.

Fast forward to today and hunting for dark matter has become extremely popular. There are now around 30 dark matter experiments around the world looking for WIMPS using crystals chilled to a few degrees above absolute zero, giant tanks of ultrapure liquid xenon and even bubble chambers. By using ultrapure materials, freezing them and shielding the detectors from cosmic rays or other radiation, these experiments simply wait for a passing WIMP to leave a signal rather than look for messy seasonal variations.

Several of them have ruled out WIMPs with the properties that DAMA claimed, most recently the COUPP experiment at Fermilab near Chicago. But the DAMA result remains a thorn in the side of dark matter hunters, which is why I think it was right to repeat the experiment using improved technology.

A physicist close to the new LIBRA collaboration says that Bernabei will announce a positive signal for dark matter. If that's true, I reckon the LIBRA result could simply spark another round of controversy, rather than silence the sceptics.

Some scientists might be horrified that I and other bloggers are spreading rumours and speculation about Bernabei's talk. But the beauty of conferences is that you can pick up on the very latest ideas as they emerge. Dark matter research is reaching fever pitch and we should all be able to share the excitement.

Friday, April 11, 2008

Is NASA's workforce too old?

There have already been some early road bumps in NASA's shift from space shuttles to their replacements in the so-called Constellation programme, but NASA officials assure us they have their finest experts on hand to tackle them.

But is that the best strategy?

Perhaps in facing the challenges of this novel space enterprise, NASA should mine the creativity and insights of its younger engineers instead of turning first to industry old-timers.

After all, youngsters at NASA have accomplished some pretty great things in the past.

"If you look back on the Apollo programme, most of that generation was probably in their 20s. Somebody in their 30s was probably in a senior position," NASA's Rick Gilbrech said this week at the National Space Symposium in Colorado Springs, Colorado, US.

The average age of NASA's workforce has been steadily increasing for the past decade and a half, according to a 2007 National Research Council report. With the average age now at 47, "we tend to have the burden of knowledge - or the curse of knowledge - that we don't tend to take a fresh look at things", Gilbrech said. Coming from Gilbrech, the associate administrator for the Exploration Systems Mission Directorate, that means something.

And NASA's graying cadre of scientists and engineers poses another, more practical problem - what will happen when they all retire?

So what should NASA and the rest of the country's space industry, which faces the same problem, do to attract more young talent? Some solutions, it would seem, would entail societal changes: more early science education to excite tomorrow's engineers and more support of the nation's space programme in the political realm, to keep those choosing a space career confident that tomorrow they'll still have a job.

But it doesn't necessarily have to be that complicated. Some NASA employees think the agency could go a long way towards attracting the interest of Generation Y just by adopting the communication trends of the day, including YouTube, Twitter, Facebook and reality television. A more interactive NASA, they say, is a more engaged public.

Equally important, though, is attracting and retaining young engineering talent. And one of the best ways to do that? Challenging them to solve exciting and difficult problems - say, for example, curing Constellation's woes.